In early Texas had Apache, Comanche, Kiowa camps and mountain lookouts. White settlement began at Camp Colorado, U.S. 2nd Cavalry post on Jim Ned Creek, 1857. County was created Feb. 1, 1858. Named for Robert M. Coleman (1799-1837), a signer of Texas Declaration of Independence and hero of the Battle of San Jacinto.
To south part of county, 1862, came John Chisum, to raise cattle to be furnished to Confederate troops fighting Civil War. County was organized Oct. 6, 1864. Courts first met at Camp Colorado. Coleman was approved as county seat April 28, 1876.